A recent study found that severe respiratory infections like COVID-19 and influenza might raise the risk of lung cancer years after recovery. Researchers say these infections can cause lasting changes in the lungs that make it easier for cancer to develop.
The research was conducted by scientists from the University of Virginia Health System and published in the scientific journal Cell.
Researchers say severe viral infections can “reprogram” immune cells in the lungs, leading to long-lasting inflammation that may encourage tumor growth.
Lead researcher Jie Sun explained that a serious case of COVID-19 or flu can leave the lungs inflamed for a long time. This ongoing inflammation can make it easier for cancer to develop later on.
The study suggests that doctors should closely monitor patients recovering from severe respiratory infections to detect early signs of lung cancer.
Findings from the Study
In lab experiments with mice, those that recovered from severe lung infections had much higher rates of lung cancer and worse survival.
Data from hospitalized patients showed a similar trend. People hospitalized with COVID-19 had a 1.24 times higher risk of lung cancer, no matter their smoking history or other health issues.
However, researchers noted that mild infections did not increase risk. In some cases, mild infections might even offer a slight protective effect.
The study found that severe viral pneumonia can change lung tissue at a biological level. These infections can alter immune cells such as neutrophils and macrophages, pushing them into dysfunctional states that support inflammation and weaken the body’s anti-cancer defenses.
Also, the epithelial cells lining the airways and alveoli may change, making them more prone to mutations.
Researchers say this ongoing inflammation is like the conditions that lead to cancer, similar to smoking’s effects. But here, the damage comes from immune system changes, not toxins.
Physician-scientist Jeffrey Sturek said the findings could change how doctors monitor patients after serious respiratory infections.
Currently, people with a heavy smoking history are often told to get regular CT scans to catch lung cancer early. In the future, similar checks might be recommended for those who had severe viral pneumonia.
Early detection is key because lung cancer is often found late, when treatment options are limited.
Vaccination May Reduce the Risk
The study also pointed out the protective role of vaccination. Researchers found that people vaccinated before infection had fewer lung changes linked to cancer risk.
Vaccines help the immune system respond more effectively to infections, which reduces the severity of illness and the long-term damage to lung tissue.
Scientists believe vaccination may not only prevent hospitalization but also reduce long-term problems from severe infections.
Global Impact of Lung Cancer
According to the World Health Organization, lung cancer remains the leading cause of cancer-related deaths worldwide. The disease affects both men and women and often goes undetected until advanced stages.
Because of this, researchers say learning about new risk factors, such as severe respiratory infections, could help doctors develop better ways to prevent and detect lung cancer early.
As millions around the world recover from serious respiratory illnesses, the study underscores the importance of long-term health monitoring and preventive care.
